function calculateWattage(restingHeartRate, maximumHeartRate, heartRate, basePowerOutput) {
    function getZonePercentile(heartRate, restingHeartRate, maximumHeartRate) {
        const HRR = maximumHeartRate - restingHeartRate;
        const zonePercentage = ((heartRate - restingHeartRate) / HRR) * 100;
        return Math.round(zonePercentage * 100) / 100;
    }

    function getHrrRange(zone) {
        if (zone <= 65) return [0, 65];
        else if (zone <= 70) return [65, 70];
        else if (zone <= 80) return [70, 80];
        else if (zone <= 85) return [80, 85];
        else if (zone <= 95) return [85, 95];
        else return [95, 100];
    }

    function getPowerRange(zone) {
        if (zone <= 65) return [0, 45];
        else if (zone <= 70) return [45, 60];
        else if (zone <= 80) return [60, 70];
        else if (zone <= 85) return [70, 80];
        else if (zone <= 95) return [80, 105];
        else return [105, 115];
    }

    const zonePercentage = getZonePercentile(heartRate, restingHeartRate, maximumHeartRate);
    console.log("Zone:", zonePercentage);

    const minPower = getPowerRange(zonePercentage)[0];
    const maxPower = getPowerRange(zonePercentage)[1];

    const [minHrr, maxHrr] = getHrrRange(zonePercentage);
    console.log("Min HRR:", minHrr);
    console.log("Max HRR:", maxHrr);

    const powerRange = maxPower - minPower;
    console.log("Power range:", powerRange);

    const hrrRange = maxHrr - minHrr;
    console.log("HRR range:", hrrRange);
    console.log("Zone minus min HRR:", zonePercentage - minHrr);

    const hrrPercentage = (zonePercentage - minHrr) / hrrRange;
    console.log("HRR percentage:", hrrPercentage);

    const powerPercentage = (minPower + hrrPercentage * powerRange) / 100;
    console.log("Power percentage:", powerPercentage);

    // Calculate predicted power
    const predictedPower = basePowerOutput / powerPercentage;

    return Math.round(predictedPower);
}

// Example usage
const restingHeartRate = 58;
const maximumHeartRate = 165;
const heartRate = 132;
const basePowerOutput = 110;

const watts = calculateWattage(restingHeartRate, maximumHeartRate, heartRate, basePowerOutput);
console.log(`Predicted power: ${watts} watts`);